Package org.verapdf.wcag.algorithms.semanticalgorithms

Class ContrastRatioChecker

java.lang.Object

org.verapdf.wcag.algorithms.semanticalgorithms.ContrastRatioChecker

public class ContrastRatioChecker
extends Object

Constructor Summary

Constructors

Constructor	Description
ContrastRatioChecker()

Method Summary

Modifier and Type	Method	Description
void	checkSemanticTree(ITree tree, String pdfName)	Traverses the document semantic tree and updates contrast ratio parameter of it's nodes.
double	getContrastRatio(double first, double second)	Determines contrast ratio of two color based on their relative luminance.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ContrastRatioChecker

public ContrastRatioChecker()

Method Details

checkSemanticTree

public void checkSemanticTree(ITree tree,
 String pdfName)

Traverses the document semantic tree and updates contrast ratio parameter of it's nodes. Uses pdf document associated with the tree to determine contrast ratio by rendering it's pages.

Parameters:

tree - tree with nodes to update with calculated contrast ratio

pdfName - String path to the pdf document associated with given tree

getContrastRatio

public double getContrastRatio(double first,
 double second)

Determines contrast ratio of two color based on their relative luminance. The resulting contrast ratio ranges from 1.0 to 21.0

Parameters:

first - relative luminance of the first color

second - relative luminance of the first color

Returns:

contrast ratio of the given colors